Masonry Magazine January 1979 Page. 18
Lubricated Bearing Surfaces and Slotted Holes in Bearing Seats of Steel Joists
Concrete Slab Over Steel Decking and Steel Joists
3/16" (4.8 mm) Diameter Metal Ties
2" (51 mm) Minimum Cavity
Steel Joist Structural Floor Assembly
FIG. 3
Concrete Slabs
Thermal strains or other movements are often blamed for cracking in masonry walls when the actual cause is the expansion or curling of the concrete slabs bearing on the walls. The curling of a concrete slab has even been known to pick up the brick bonded to it. Unfortunately, this behavior of concrete is frequently overlooked by the designer in detailing the structure.
Figure 2 illustrates a typical detail that will relieve this condition. In this design, the bond is broken between the concrete slab and the brick wall by building paper. This permits the slab to have some freedom of movement with respect to the wall. In addition, it permits the longitudinal thermal and moisture movements to occur without distress. The slab is thickened into a beam over the interior wythe to help stiffen the slab and minimize curling. Under certain climatic conditions, provisions must be made for insulation which has not been shown.
Solid Bridging at Anchor
Lateral Support Metal Anchors @8 (2.44 m) O.C. Maximum
3/16" (4.8 mm) Wall Ties at First Course Below Joist
Anchorage of Wood Floor to Cavity Wall
FIG. 4
Wood Plate
Brick Header Course
Joist Anchors at Every 4th Joist
3/16" (4.8 mm) Diameter Metal Ties
Steel Anchor Bolt with Steel Plate
2 (51 mm) Minimum Cavity
4" (102 mm) Hollow Brick or CMU
Steel Anchor Bolt Grouted into Core
2" (51 mm) Minimum Cavity
Anchorage of Wood Roof Framing to Cavity Walls
FIG. 5